Japanese Laid-Open Patent Publication No. 2003-117488 discloses a technology belonging to such a field. An oscillating actuator disclosed in Japanese Laid-Open Patent Publication No. 2003-117488 is made of a magnetic material and has a cylindrical frame. A pair of brackets is fitted in an axial outer end of the cylindrical frame. A fixed shaft is fixed to each bracket so as to movably support a mover in an axial direction. A cylindrical coil formed by a wire wound in an identical direction on a circumference is fixed on an inner peripheral surface of the frame. The mover includes a cylindrical magnet, which is disposed within a gap of the coil and magnetized along a radial direction, and a pair of bearings, which is arranged on axial opposite ends of the magnet and is made of sintered alloys with which a lubricant is impregnated. A pair of coil springs is disposed between the mover and the pair of brackets.
Further, an oscillator having a high performance can be achieved by fully magnetizing a cylindrical magnet by using a magnet having a large energy product, for example, an NdFeB-based sintered magnet. However, in a small-sized oscillator, a single pole magnetization in a radial direction is very difficult to achieve because of self-saturation of the magnetizer. Therefore, the cylindrical magnet is obtained by dividing a cylindrical magnetic body into two or three magnetic pieces in the circumferential direction, magnetizing each of the magnetic pieces in the thickness direction, and then reconstructing the divided magnetic pieces (magnet parts) with an adhesive agent. According to this method, since each of the divided magnetic pieces is independently fully magnetized, the reconstructed cylindrical magnet has an improved performance. Especially, use of an anisotropic magnet in the thickness direction is further effective and can achieve an oscillating actuator having a high performance.